A laser rangefinder is an instrument that uses lasers to accurately measure the distance to a target. When the laser rangefinder is working, it emits a very thin laser beam to the target, and the photoelectric element receives the laser beam reflected by the target. The timer measures the time from emission to reception of the laser beam and calculates the distance from the observer to the target.

If the laser is continuously emitted, the measurement range can reach about 40 kilometers, and it can be operated day and night. If the laser is pulsed, the accuracy is generally low, but better relative accuracy can be obtained in long-distance measurement.

A laser in the world was successfully developed in 1960 by Mayman, a scientist at Hughes Aircraft Corporation of the United States. On this basis, the US military quickly launched research on military laser devices. In 1961, a military laser rangefinder passed a demonstration test by the U.S. military, and the laser rangefinder soon became a practical combination.

The laser rangefinder is light in weight, small in size, simple to operate, fast and accurate, and its error is only one-fifth to one-hundredth of other optical rangefinders. Therefore, it is widely used in topographic surveying, battlefield surveying, tanks, etc. Range measurement of targets by aircraft, ships and artillery, as well as measurement of the height of clouds, aircraft, missiles and satellites. It is an important technical equipment to improve the accuracy of high tanks, aircraft, ships and artillery.

Due to the continuous downward adjustment of the price of laser rangefinders, laser rangefinders are gradually being used in the industry. A number of new miniature rangefinders have emerged at home and abroad, which have the advantages of fast ranging speed, small size, and reliable performance. They can be widely used in industrial measurement and control, mines, ports and other fields.